So I'm sure a lot of people are discovering their GNUMP3d GUI
preferences no longer being saved. It looks like the cookies
responsible for saving the preferences were hardcoded to expire Mon,
10-Mar-08 14:36:42 GMT, which has just passed, thereby causing the
ability to save preferences to break.

Although, this should probably be changed to work differently, you can
easily work around this problem by simply editing the gnump3d script
(/usr/bin/gnump3d in the Debian/Ubuntu packages) and changing the date
the cookie sets to a date that's pretty far in the future.